Cutout construction



July 4, 1950 w. o. scHULTz cuToufr CONSTRUCTION 4 Sheets-Sheet 3 FiledApril 28, 1947 /l kj/ 4 27 30 July 4, 1950 w. o. scHuL'rz cuTou'rCONSTRUCTION 4 Sheets-Sheet 4 Filed April 281947 Orne? Y disclosedtending outwardly Patented .ulgy 4, 1950 UNITED STATES PATENT AOFFICECUTOUT CONSTRUCTION William 0. Schultz, South Milwaukee, yWis., as-

signor to McGraw Electric Gompany,.a corporation of Delaware ApplicationApril'28, 1947,-Serial No. '144,472

5 Claims. 1 This.inventionrelates to a cutout construction. '.Thisinvention is van improvement over that in `my United States Patent No.2,372,126 of .March 20, 1945, for Drop-Out Fuse I Device.

yIn general, this invention has the same ob ,jects as those set forth inmy above noted patent.

Further objects are to provide a cutout com struction of a .drop-outtype in which the upper stationary contact is a rigid member of simplelconstruction, in which the lower stationary con- .tact'consists ofaheavy U-shaped member makingonly line contact with the contact carriedyby the dcoig. and'in which resiliency is provided between .theuppenrigid stationary vcontact and Athe upper Contact ofthe cutout by meansof .a

floating spring pressed lever.

.Morespecically,.further objects are to provide a housed type ofdrop-.outfuse cutout in Vwhich the upper stationary contact of thehousingiisrigid and in which arigid lower contact is carried by theVdoor andengages and is held link .upon rupture thereof, but also actsinthe dual capacity oi providing heavy substantially Aline` contact withthe lower contact of the door, and a'lsorwhich` provides, together .withthe auxil- Viary lever, a yielding heavy pressure between the upperContact of the :fuse tube and .the upper stationary contact, .theconstruction being such thatafterrupture of the fuse link the throwout'lever detachee itself from the lower contact 4of the door and movesdownwardly with the fuse tube and is electrically dead'in its iinal.position -so that there are no live projecting parts ex from the bottomof the housing.

An embodiment of the invention is shown in the accompanying drawings, inwhich:

Figure l is a side elevation partly broken away and partly in sectionshowing the fusek in its uppermost or operative position.

Figure 2 is a bottom view of the structure shown in Figure 1.

Figure 3 is a top view of the device with parts brokenl away andparts insection.

vFigure l is a sectional view on the line 1 -4 of Figure 1, such Viewbeing approximately a line section.

.Figure 5,is.a sectional View approximately on thelineS-E of Figure 1.

Figure 6 is a sectional view approximately'on .therlinec-B-:G.of..Figure 1.

Figure? isa fragmentary sectional Viev/.partiy broken away of the lowerportion vof the cutout.

vFigure 8 is -a `view .showingan intermediate position yof the lower.mechanism .immediately altery rupture ofthey fuse link.

.Figure .Qshows the'final inoperative or .cir-

.cuit-open rposition.

Referringto Jthe;drawings, it will .be seenthat Vthe cutout comprises ahousing il of insulating .material anda door-2.also of insulatingmaterial .and preferably rsupported `from thehousing .by .meansoftrunnionsii carriedlbythe lower con- :tactiIi-oithe door-.2 andremovably seatedwithin hook-like spaced v.portions ..5 Vcarried :by 'thehousing.

:The lower .stationary contact .or terminal v,of

ithe housing .consists :of .a heavy yielding AU- .rigidU-shaped member 8.carried by the housing A.and provided 4with 4conical .recessed portions;9 .in the lower` .edges .of the arms of this- U-shaped Amember' YB.

The fupper and Alower terminalspare .each provided .with .a rigidtransverse ,bar .I0 Ivwhich.isgroovedon its rear .side and.is adapted.tube respectivelyengaged by the line and load .conductors ii land t2,suitable clamping means I3 .being provided. It isalsopreferabletoprovide a barrier v t4 formedintegrally with the housing I and locatedbetween the upper and .lower stationary terminals.

Therese tube isformed .of insulating mate- .rial and is indicated bythe;reference character .UL `It isprovided with an upper terminalvllwhicli has outwardly projecting rigid, conical ears or members Iiiwhich iit Within-the conical recesses -Brof ythe rigid upper stationaryContact v8. It isprovided with ythe usual screw cap i1 for lockingthe-button on the fuse link in place as shown in my -fabovenoted patent.The upper terminal ofthe fuse tube is provided with apair lof laterallyprojecting arms I8, see Figure 3, ywhich ride against ribs or portionsI9 formed integrally with the door. `minal i5 of the fuse tubeisprovided with .an .outwardly projecting tongue 2D which is posi-Further the upper tertioned between the ribs i9 but which has plenty -of.lateral play as maybe seen from Figure .3, 55-

.so as toleave theupper terminal of thefuse tube carried by the door.

free to adjust itself accurately to the conical recesses 9 formed in theupper stationary terminal 3 of the housing. The ribs I9 extenddownwardly but approach each other to provide a relatively narrower slot2I therebetween for guiding the tongue 29 downwardly centrally of thedoor when the fuse tube drops downwardly to its inoperative position.

The lower terminal 4 of the door loosely guides the fuse tube I4 andallows it to slide downwardly from the position shown in Figure 1 to itsfinal position shown in Figure 9 upon rupture of the fuse link, suchfuse link being indicated generally by the'reference character 22. Thelower contact 4 of the door is provided with a box-like lower portionindicated by the reference character 4. This box-like portion 4isprovided with a rear slanting wall 23 which is formed of a pair ofinwardly shaped fingers formed integrally with the lower contact of thedoor.

' which an auxiliary lever 26 is pivoted. This auxiliary lever is springpressed in a counter-clockwise direction by means of the spring 21 andis provided with a pair of forwardly projecting fingers 28 which engagethe collar 24 when the fuse link blows and the auxiliary lever moves tothe position shown in Figures 8 and 9. The auxiliary lever carries afloating lever or throw-out lever 29 adjacent its inner end. Thefloating lever or throw-out lever 29 is provided with a threaded stud 30and a thumb nut 3| for clamping the leader of the fuse link 22 in place.

It is to be noted from reference to Figure 7 that the throw-out lever orfloating lever 29 is provided with a rearwardly projecting ear 32 whichengages the slanting wall 23 of the lower contact 4 of the door with aheavy pressure and has substantially line contact therewith.

It is to be noted that when the leaderl of the fuse link 22 is clampedto the throw-out lever 29 and the parts are in the position shown inFigure 7, that the arm or ear 32 of the throw-out lever acts as afulcrum against the wall 23 and holds vthe intermediate or auxiliarylever 26 in its stressed position shown in Figure 7. This urges theconical ears I6 of the upper terminal I5 of the fuse tube against therigid stationary terminal 8 and provides heavy contact pressure at thatpoint, it being noted that heavy Contact pressure is obtained betweenthe arm 32 of the throwout lever and the wall 23 of the lower terminal 4of the door. To express this in other words, it is apparent from anexamination of Figure 7 that the left-hand end of the lever 26 is thrustdownwardly by means of the spring 2l and tends to force the lever 29downwardly. The right-hand end, of the lever 29 is prevented fromdownward motion by being secured to the fuse link. The left-hand end orportion 32 of the lever 29 therefore tends to move downwardly andpresses downwardly against the portion 23 of the terminal 4Consequently, there is an upward thrust imparted to the fuse tube I4which ytends to force the fuse tube I4 upwardly and thereby forces itsupper contacts or conical ears I6 against the upper stationary terminal8 carried by the housing. Heavy contact pressure is also obtainedbetween the stationary lower terminal 6 of the housing and the lowerterminal 4 of the door, The current is transferred directly from thefuse link to the throw-out lever and through the heavy line contactbetween the arm 32 and the wall 23 to the lower terminal 4 of the door.

Upon rupture of the fuse link, the throw-out lever or fuse linkextracting lever 29 rocks in a clockwise direction, being urged towardsthis motion by means of the spring pressed auxiliary lever 26. Thethrow-out lever 29 is a iloating lever and its fulcrum or arm 32 rocksand slides along the slanting walls 23 of the lower terminal 4 of thedoor and nally passes from the wall 23 and allows the fuse tube to dropdownwardly to its inoperative position shown in Figure 9. It is to benoted that when the parts are in this iinal position, that allprojecting parts carried by the fuse tube are electrically dead and,therefore, there is no resulting hazard as would have been the case hadthe parts been live.

It will be seen that a novel form of cutout construction has beenprovided wherein heavy contact pressure is obtained between the rigidstationary contact of the housing and the rigid contact or upperterminal of the fuse tube and wherein substantially line contact hasbeen obtained between the lower stationary terminal and the terminalcarried by the door, and in which a system of levers is provided wherebya floating throw-out lever not only extracts any remaining portion ofthe fuse link upon rupture thereof and also furnishes the upward thruston the fuse tube to secure the heavy contact pressure between the upperterminal of the fuse tube and the upper stationary terminal, the leverconstruction being such that all parts projecting from the housingfollowing rupture of the fuse link are electrically dead in the finalinoperative position of the fuse tube.

It is to be noted that the auxiliary lever and the throw-out lever areboth normally housed within the sleeve and are thus quite well protectedagainst striking any of the parts of the housing when the door is beingreplaced.

Although this invention has been described in considerable detail, it isto be understood that such description is intended as illustrativerather than limiting, as the invention may be variously embodied and isto be interpreted as claimed.

I claim:

1. A drop-out cutout comprising a rigid upper stationary terminal and alower stationary terminal, a movable tubular member of insulatingmaterial having an upper rigid terminal normally engaging said upperstationary terminal, circuit interrupting means within said tubularmember connected t0 the upper terminal of said tubular member,stationary means, and mechanism including a downwardly spring pressedfloating lever supported from the lower portion of said tubular memberand normally restrained from motion by said circuit interrupting meansand engaging said stationary means to restrain said tubular member frommotion and arranged to release said tubular member when said circuitinterrupting means functions, said mechanism being arranged toyieldingly hold the terminal of said tubular member in engagement withsaid rigid upper stationary terminal.

2. A drop-out fuse construction comprising a rigid upper stationaryterminal, a lower stationary terminal, a fuse tube having a fuse linktherein and having an upper terminal connected thereto and normallyengaging said rigid upper stationary terminal, a sleeve for guiding saidfuse tube, said sleeve being normally connected to said lower stationaryterminal, and a floating, downwardly spring pressed lever supported fromsaid fuse tube and housed within said sleeve and having one endconnected to said fuse link and having the other end supported from theinterior of said sleeve, said floating lever being arranged to urge theterminal of said fuse tube into engagement with said rigid upperstationary terminal.

3. A housed type drop-out fuse construction comprising a housing, a doorfor said housing,

said door having a sleeve constituting a lower terminal, a lowerstationary terminal having a pair of spring arms arranged to engage thelower terminal of said door and having a line contact therewith, anupper stationary terminal, a fuse tube slidably carried by said sleeveand having an upper terminal normally engaging said upper stationaryterminal with a direct upward thrust, and spring biased throw-out meansrestrained by said fuse link and arranged to impart an upward thrust tosaid fuse tube and to electrically connect with said sleeve and beingnormally housed within said sleeve.

4. A housed type drop-out fuse construction comprising a housing, a doorfor said housing,

said door having a sleeve constituting a lower terminal, a lowerstationary terminal having a pair of spring arms arranged to engage thelower terminal of said door and having a line Contact therewith, anupper stationary terminal, a fuse tube slidably carried by said sleeveand having an upper terminal normally engaging said upper stationaryterminal with a direct upward thrust, and spring biased throw-out meansrestrained by said fuse link and arranged to impart an upward thrust tosaid fuse tube and to electrically con- 3 nect with said sleeve andhaving a line contact therewith and arranged to release said fuse tubefor downward sliding motion and detach itself from said sleeve onrupture of said fuse link.

5. A drop-out fuse construction comprising upper and lower stationaryterminals, a fuse tube having an upper terminal normally interlockingwith the upper stationary terminal and detachable therefrom, a fuse linkextending downwardly from the upper terminal of said fuse tube andprojecting outwardly through the lower end thereof, a sleeve-like memberslidably supporting said fuse tube and normally engaging said lowerstationary terminal, a spring pressed lever pivotally supported from thelower portion of said fuse tube and having a free end biased downwardly,a throw-out lever pivoted intermediate its ends on the free end of saidspring pressed lever and having one end detachably interlocking withsaid sleeve-like member and having pressure contact therewith and havingthe fuse link extending over the other end thereof, said throw-out leverconstituting a floating lever and coacting with said spring pressedlever to allow said fuse tube to slide downwardly a slight distance whensaid fuse tube is moved into operative position, said spring pressedlever and said throw-out lever being arranged to transmit upward thrustto said fuse tube to thereby hold the upper terminal of said fuse tubein pressure and interlocking contact with said upper stationaryterminal.

WILLIAM O. SCHULTZ.

REFERENCES CITED The following references are of record in the rile ofthis patent:

UNITED STATES PATENTS Number Name Date 2,231,599 Schultz Feb. 11, 19412,357,772 Schultz Sept. 5, 1944 2,372,126 Schultz -n Mar. 20, 1945

